Enhanced discontinuous mode operation with shared radio frequency resources

ABSTRACT

A scheduling technique is described for discontinuous transmission and reception. The scheduling technique may be implemented in a mobile communication device with multiple SIMs. The scheduling technique facilitates enhanced communication capability for the mobile communication device. In one implementation, the scheduling technique helps avoid substantial overlap between discontinuous receive cycles of the SIMs, for example by renegotiating a discontinuous transmit/receive offset if too much overlap exists. The renegotiation process may be incorporated into a future industry standard communication protocol (e.g., 3GPP release 11 or later), or may be implemented as an extension to an existing communication protocol.

1. PRIORITY CLAIM

This application claims the benefit of priority to the following U.S.provisional patent applications:

-   U.S. Patent Application No. 61/569,621, filed 12 Dec. 2011, under    attorney docket number 14528.00045;-   U.S. Patent Application No. 61/587,521, filed 17 Jan. 2012, under    attorney docket number 14528.00425; and-   U.S. Patent Application No. 61/595,546, filed 6 Feb. 2012, under    attorney docket number 14528.00460.

2. TECHNICAL FIELD

This disclosure relates to communication devices with multipleSubscriber Identity Modules (SIMs). The disclosure also relates toenhanced discontinuous transmit and receive mode operation when radiofrequency resources are shared between SIMs.

3. BACKGROUND

Rapid advances in electronics and communication technologies, driven byimmense customer demand, have resulted in the widespread adoption ofmobile communication devices. The extent of the proliferation of suchdevices is readily apparent in view of some estimates that put thenumber of wireless subscriber connections in use around the world atnearly 80% of the world's population. Furthermore, other estimatesindicate that (as just three examples) the United States, Italy, and theUK have more mobile phones in use in each country than there are peopleliving in those countries.

Relatively recently, cellular phone manufactures have introduced phonedesigns that include multiple SIM cards. Each SIM card facilitates aseparate connection to the same network or different networks. As aresult, the SIMs provide the owner of the phone with, for example, twodifferent phone numbers handled by the same phone hardware. Accordingly,the multiple SIM approach alleviates to some degree the need to carrydifferent physical phones, and improvements in multiple SIMcommunication devices will continue to make such devices attractiveoptions for the consumer.

BRIEF DESCRIPTION OF THE DRAWINGS

The innovation may be better understood with reference to the followingdrawings and description. In the figures, like reference numeralsdesignate corresponding parts throughout the different views.

FIG. 1 shows an example of user equipment with multiple SIMs.

FIG. 2 shows a timing example of DTX scheduling.

FIG. 3 shows a timing example of DRX scheduling.

FIG. 4 is an example of a timing diagram that shows the overlap in theSIM1 DRX pattern and the SIM2 DRX pattern.

FIG. 5 is an example timing diagram that shows the effect of the userequipment negotiating a change the DRX parameters.

FIG. 6 shows a timing diagram showing the result of the shift in theSIM2 DRX pattern.

FIG. 7 shows an example timing diagram 700 that continues the exampleshown in FIG. 2.

FIG. 8 shows a timing diagram in which the user equipment has negotiatedwith the Node B to shift the SIM2 DTX pattern ahead three subframes.

FIG. 9 shows discontinuous mode enhancement logic (DMEL).

FIG. 10 shows an example of a network controller 1000 that supportsDTX/DRX negotiation.

FIG. 11 shows an example of the DTX/DRX parameter negotiation logic(PNL) that may be implemented at the network controller.

DETAILED DESCRIPTION

The discussion below makes reference to user equipment. User equipmentmay take many different forms and have many different functions. As oneexample, user equipment may be a cellular phone capable of making andreceiving wireless phone calls. The user equipment may also be asmartphone that, in addition to making and receiving phone calls, runsgeneral purpose applications. User equipment may be virtually any devicethat wirelessly connects to a network, including as additional examplesa driver assistance module in a vehicle, an emergency transponder, apager, a satellite television receiver, a networked stereo receiver, acomputer system, music player, or virtually any other device. Thediscussion below addresses how to manage discontinuous mode receptionand transmission in user equipment that includes multiple (e.g., two)SIMs.

FIG. 1 shows an example of user equipment 100 with multiple SIMs, inthis example the SIM1 102 and the SIM2 104. An electrical and physicalinterface 106 connects SIM1 102 to the rest of the user equipmenthardware, for example, to the system bus 110. Similarly, the electricaland physical interface 108 connects the SIM2 to the system bus 110.

The user equipment 100 includes a communication interface 112, systemlogic 114, and a user interface 118. The system logic 114 may includeany combination of hardware, software, firmware, or other logic. Thesystem logic 114 may be implemented, for example, in a system on a chip(SoC), application specific integrated circuit (ASIC), or othercircuitry. The system logic 114 is part of the implementation of anydesired functionality in the user equipment 100. In that regard, thesystem logic 114 may include logic that facilitates, as examples,running applications, accepting user inputs, saving and retrievingapplication data, establishing, maintaining, and terminating cellularphone calls, wireless network connections, Bluetooth connections, orother connections, and displaying relevant information on the userinterface 118. The user interface 118 may include a graphical userinterface, touch sensitive display, voice or facial recognition inputs,buttons, switches, and other user interface elements.

The communication interface 112 may include one or more transceivers.The transceivers may be wireless transceivers that includemodulation/demodulation circuitry, amplifiers, phase locked loops(PLLs), clock generators, analog to digital and digital to analogconverters and/or other logic for transmitting and receiving through oneor more antennas, or through a physical (e.g., wireline) medium. Thetransmitted and received signals may adhere to any of a diverse array offormats, protocols, modulations, frequency channels, bit rates, andencodings. As one specific example, the communication interface 112 maysupport transmission and reception under the Universal MobileTelecommunications System (UMTS). The techniques described below,however, are applicable to other communications technologies regardlessof whether they arise from the 3rd Generation Partnership Project(3GPP), GSM® Association, Long Term Evolution (LTE)™ efforts, or otherpartnerships or other standards bodies.

Existing communication standards define a discontinuous receive mode(DRX) and a discontinuous transmit mode (DTX) for the user equipment100. One goal of DRX/DTX is to extend battery life by not constantlyreceiving or transmitting on, for example, the radio resource controlchannels during the entire time that the user equipment 100 is assignedthe radio resource. Instead, the user equipment 100 may regularly enterpower saving states that significantly reduce power consumption of theuser equipment 100. In the power saving states, the radio frequency (RF)modems and other system logic consume significantly less power.

The DTX/DRX modes are particularly beneficial when the user equipment100 has relatively low activity on the radio frequency (RF) channel thatmay result because the user equipment 100 is carrying out functions thatonly infrequently send or receive data. As a specific example of DTX,the user equipment 100 may enter a power saving mode during thesometimes frequent periods of silence in a voice conversation. DRX isalso beneficial when a particular SIM is not in connected mode.Specifically, instead of the disconnected SIM waking up to listen forpages for the entire duration of the entire paging channel, the SIM mayonly wake and receive its assigned subchannels in the paging channel todetermine if the SIM is being paged. In between the assignedsubchannels, the user equipment 100 may be able to enter a power savingmode.

In one implementation, the system logic 114 includes one or moreprocessors 116 and a memory 120. The memory 120 stores, for example,scheduling instructions 122 that the processor 114 executes. SIM1 102and SIM2 104 may be on the same or different networks, and may be servedby the same or different cells. For example, the Node B 128 may manage aparticular cell to which SIM1 102 is connected, while the Node B 129 maymanage a different cell to which SIM2 104 is connected. Accordingly, theDTX/DRX modes may be established for each of SIM1 and SIM2independently. The user equipment 100 may stores a set of DTX/DRXparameters for each of the SIMs in the memory 120 as the SIM1 DRX/DTXparameters 124 and the SIM2 DRX/DTX parameters 126. The Node Bs 128 and129 (e.g., UMTS network base stations) can signal the DTX/DRX parametersto the user equipment 100 through Information Elements in a controlchannel, for example. As mentioned above, the Node B 128 may be part ofa network that supports SIM1 102, while the Node B 129 may be part ofthe same or different network that supports SIM2 104. As will bedescribed in more detail below, the system logic 114 will try to reduceinefficient DTX/DRX overlap between SIM1 102 and SIM2 104. Suchinefficiencies sometimes result because the different networks thatassign the DTX/DRX parameters typically do not coordinate betweenthemselves when assigning the parameters.

Examples of the DRX/DTX parameters 124 and 126 include DRX/DTX offset,DRX/DTX cycle information, and other parameters such as those shown insections 10.3.6.34a “DTX-DRX information” and 10.3.6.34b “DTX-DRX timinginformation”, in the 3GPP V9.6.0 Radio Resource Control (RRC) Protocolspecification, and further explained in section 6C “Discontinuoustransmission and reception procedures” in the 3GPP V9.5.0 Physical LayerProcedures (FDD) document. Before turning to the scheduling techniquesin detail, a short summary of the DTX/DRX parameters are given next inTable 1 with accompanying explanation. Below, E-DCH is a reference to anEnhanced Dedicated Channel, while TTI is a reference to TransmissionTime Interval, a UMTS parameter that specifies duration forencapsulating data from higher layers into frames for transmission onthe radio interface, as examples, frames of length 2 ms, 10 ms, 20 ms,40 ms, or 80 ms.

Examples of DTX/DRX Parameters

TABLE 1 exemplary DTX/DRX parameters Information Element/Group name Typeand reference DTX Information >CHOICE E-DCH TTI length >>10 ms >>>UE DTXcycle 1 Enumerated (1, 5, 10, 20) subframes >>>UE DTX cycle 2 Enumerated(5, 10, 20, 40, 80, 160) >>>MAC DTX cycle Enumerated (5, 10, 20)subframes >>2 ms >>>UE DTX cycle 1 Enumerated (1, 4, 5, 8, 10, 16, 20)subframes >>>UE DTX cycle 2 Enumerated (4, 5, 8, 10, 16, 20, 32, 40, 64,80, 128, 160) subframes >>>MAC DTX cycle Enumerated (1,4, 5, 8, 10, 16,20) subframes >Inactivity Threshold for UE DTX Enumerated (1, 4, 8, 16,32, 64, 128, 256) cycle 2 E-DCH TTIs >Default SG in DTX Cycle 2 Integer(0 . . . 37, 38) Serving Grant value to be used at the transition inDTX-Cycle-2. (0 . . . 37) indicates E-DCH serving grant index as definedin [15]; index 38 means zero grant. >UE DTX long preamble lengthEnumerated (4, 15) slots >MAC Inactivity Threshold Enumerated (1, 2, 4,8, 16, 32, 64, 128, 256, 512, Infinity) E-DCH TTIs >CQI DTX TimerEnumerated (0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, Infinity)subframes >UE DPCCH burst_1 Enumerated (1, 2, 5) subframes >UE DPCCHburst_2 Enumerated (1, 2, 5) subframes DRX Information >UE DRX cycleEnumerated (4, 5, 8, 10, 16, 20) subframes >Inactivity Threshold for UEDRX Enumerated (0, 1, 2, 4, 8, 16, 32, 64, 128, cycle 256, 512)subframes >Inactivity Threshold for UE Grant Enumerated (0, 1, 2, 4, 8,16, 32, 64, 128, Monitoring 256) E-DCH TTIs >UE DRX Grant MonitoringBoolean Uplink DPCCH slot format information Enumerated (1, 4) Slotformat # to be used on UL DPCCH. CHOICE timing >Continue (no data) >Newtiming >>Enabling Delay Enumerated (0, 1, 2, 4, 8, 16, 32, 64, 128)radio frames >>UE DTX DRX Offset Integer (0 to 159) subframes. Offset ofthe DTX and DRX cycles at the given TTI.

Regarding the parameters in Table 1, for discontinuous transmission,e.g., discontinuous uplink (UL) Dedicated Physical Control Channel(DPCCH) transmission:

CQI_DTX_TIMER: Specifies the number of subframes during which theChannel Quality Indicator (CQI) reports have higher priority than theDTX pattern. This is the initial value of CQI nominal reporting timer.

UE_DTX_cycle_(—)1: Specifies the UL DPCCH burst pattern length insubframes.

UE_DTX_cycle_(—)2: Specifics the UL DPCCH burst pattern length insubframes.

Inactivity_Threshold_for_UE_DTX_cycle_(—)2: Defines a number ofconsecutive E-DCH TTIs without an E-DCH transmission, after which theuser equipment 100 moves from UE_DTX_cycle_(—)1 to usingUE_DTX_cycle_(—)2.

UE_DPCCH_burst_(—)1: Determines the Uplink DPCCH burst length insubframes, when UE_DTX_cycle_(—)1 is applied.

UE_DPCCH_burst_(—)2: Determines the Uplink DPCCH burst length insubframes, when UE_DTX_cycle_(—)2 is applied.

UE_DTX_long_preamble_length: Determines in slots the length of thepreamble associated with the UE_DTX_cycle_(—)2.

For both discontinuous UL DPCCH transmission and discontinuous downlinkreception:

UE_DTX_DRX Offset: Determines the UL DPCCH burst pattern and HS-SCCHreception pattern offset in subframes.

Enabling_Delay: ensures that the uplink DPCCH and downlink F-DPCH aretransmitted continuously for Enabling_Delay radio frames afterDTX_DRX_STATUS is set to TRUE or ensures that, with DTX_DRX_STATUS setto TRUE, the uplink DPCCH on the secondary uplink frequency istransmitted continuously for Enabling_Delay radio frames afterapplication of secondary uplink frequency activation.

For discontinuous downlink reception:

UE_DRX cycle: Determines the HS-SCCH reception pattern length insubframes.

Inactivity_Threshold_for_UE_DRX_cycle: Defines the number of subframesafter an HS-SCCH reception or after the first slot of an HS-PDSCHreception during which the user equipment 100 monitors the HS-SCCHs inthe user equipment's HS-SCCH set with the exceptions ofN_acknack_transmit>1 or InterTTI>1.

UE_DRX_Grant_Monitoring: A Boolean which determines whether the userequipment is required to monitor the E-AGCH transmissions from theserving E-DCH cell and the E-RGCH from cells in the serving E-DCH radiolink set when certain conditions are met.

Example Discontinuous Timing Patterns

FIG. 2 shows a timing example of DTX scheduling 200 for SIM1 102 and forSIM2 104. Each SIM may have different DTX and DRX patterns because eachSIM may be connected to different networks that supply different timingparameters. For example, the SIM1 102 may receive its parameters fromthe Node B 128 and SIM2 104 may receive its parameters from the Node B129. FIG. 2 shows a radio frame 202 which in this example is 10 ms long,and an example DTX uplink burst pattern 204 for SIM1 102. The uplinkburst pattern 204 shows that SIM1 102 transmits discontinuously duringthe radio frame 202. In particular, in this example, the DTX parametershave established that SIM1 will only transmit during the first subframein each radio frame 202. In other subframes, the SIM1 102 does nottransmit and the user equipment 100 may enter a low power mode if theradio resource otherwise remains unused.

FIG. 2 also shows that SIM2 104 has its own DTX timing. In particular,SIM2 104 also has its own radio frame 206, and the timing need not bethe same as the timing for SIM1 102. SIM2 also has its own uplink burstpattern 208. The uplink burst pattern 208 may be established by thetiming parameters provided by the Node B 129, for example. Similarpatterns exist for the DRX mode of operation, as will be described inmore detail below.

Section 6C, titled Discontinuous transmission and reception procedures,in the 3GPP V9.5.0 Physical Layer Procedures (FDD) document explains theway in which the DRX/DTX parameters establish the DRX and DTX patterns.However, the techniques described in this document are not limited toany particular way of defining the DRX or DTX patterns based on the DRXand DTX parameters. Just as an example to help illustrate the DRX andDTX pattern determination, Table 2 summarizes how the DTX patterns aredetermined under Section 6C and Table 3 summarizes how the DRX patternsare determined under Section 6C for high speed shared control channels(HS-SCCH). Tables 2 and 3 also highlight one way in which the UE_DTX_DRXOffset parameter shifts the DTX and DRX patterns by moving the firstsubframe in the uplink burst or the subframes that are received.

TABLE 2 Summary of DTX pattern determination The Uplink DPCCH burstpattern may define a minimum set of slots (e.g., subframes) in which theuser equipment transmits (e.g., transmits a UL-DPCCH). The UL DPCCHburst pattern may be derived as follows: 1) With no E-DCH transmissionfor the last Inactivity_Threshold_for_UE_DTX_cycle_2 E- DCH TTIs, and atleast this many TTIs have passed since the end of the Enabling_Delay,then: 1a) The transmission length in the Uplink DPCCH burst pattern is:UE_DPCCH_burst_2 subframes. 1b) The gap length following the DPCCHtransmission burst in the Uplink DPCCH burst pattern is: (UE_DTX_cycle_2− UE_DPCCH_burst_2) subframes, 1c) The first subframe in each UplinkDPCCH burst pattern shall be such that the CFN and DPCCH subframe numberS satisfy: ((5*CFN − UE_DTX_DRX_Offset + S) MOD UE_DTX_cycle_2) = 0 2)Otherwise: 2a) The transmission length in the Uplink DPCCH burst patternis: UE_DPCCH_burst_1 subframes. 2b) The gap length following the DPCCHtransmission burst in the Uplink DPCCH burst pattern is: (UE_DTX_cycle_1− UE_DPCCH_burst_1) subframes. 2c) The first subframe in each UplinkDPCCH burst pattern shall be such that the CFN and DPCCH subframe numberS satisfy: ((5*CFN − UE_DTX_DRX_Offset + S) MOD UE_DTX_cycle_1) = 0

TABLE 3 Summary of DRX pattern determination The HS-SCCH receptionpattern may be derived from discontinuous reception subframe numberingusing the following assumptions, where CFN is a reference to theConnection Frame Number and HS-PDSCH is a reference to the high speedphysical downlink shared channel: 1) The discontinuous HS-SCCH receptionsubframe numbering is such that: a) A HS-SCCH discontinuous receptionradio frame is 10 ms long and is indexed using CFN_DRX. b) The start ofthe HS-SCCH discontinuous reception radio frame of CFN_DRX n is alignedwith the start of the HS-SCCH subframe that starts τDRX chips after thestart of the associated downlink F-DPCH of Connection Frame Number (CFN)n. c) The HS-SCCH subframe S_DRX = 0 is aligned with the start of theHS-SCCH discontinuous reception radio frame. The HS-SCCH subframes arenumbered S_DRX = 0 to S_DRX = 4. d) The HS-PDSCH discontinuous receptionradio frame of CFN_DRX n starts τHS- PDSCH chips after the start of theHS-SCCH discontinuous reception radio frame of CFN_DRX n. The HS-PDSCHsubframe S_DRX = 0 is aligned with the start of the HS- PDSCHdiscontinuous reception radio frame. The HS-PDSCH subframes are numberedS_DRX = 0 to S_DRX = 4. e) The HS-DPCCH discontinuous transmission radioframe of CFN_DRX n starts at the HS-DPCCH subframe boundary closest intime to 1280 chips after the start of the HS- SCCH discontinuousreception radio frame of CFN_DRX n as received at the UE. The HS-DPCCHsubframe S_DRX = 0 is aligned with the start of the HS-DPCCHdiscontinuous transmission radio frame. The HS-DPCCH subframes arenumbered S_DRX = 0 to S_DRX = 4. 2) The HS-SCCH reception pattern is theset of subframes whose HS-SCCH discontinuous reception radio framenumber CFN_DRX and subframe number S_DRX satisfy: ((5*CFN_DRX −UE_DTX_DRX_Offset + S_DRX) MOD UE_DRX cycle) = 0

Enhanced Discontinuous Mode Operation

In some implementations of the user equipment 100, the SIMs share radiofrequency resources, including the transmit/receive paths in thecommunication interface 122. As a result, both SIMs cannot receive atthe same time or transit at the same time. Instead, the user equipment100 allows the SIMs to share the radio frequency resources in a timedivision manner.

Sharing the radio frequency resources, in combination with DTX/DRX, canlead to situations in which the radio frequency resources are used lessefficiently than they might otherwise be used. FIG. 3 shows timingdiagrams 300 for DRX scheduling. The timing diagrams 300 show the SIM1radio frame 302, and the five subframe HS-SCCH channel 304 within theradio frame 302. The DRX parameters received from the Node B 128 haveconfigured the radio access for SIM1 102 to provide a DRX pattern 306through which the SIM1 102 receives every fourth subframe of the HS-SCCHchannel 304. In other words, UE_DRX_Cycle=4. In this example, SIM1 102only needs to be active on the radio resources to receive one out ofevery four HS-SCCH frames.

Similarly, SIM2 104 operates with a 10 ms radio frame 308, which is nottypically synchronized in time with the SIM1 radio frame 302. The DRXparameters received from the Node B 129 have also configured the SIM2104 to receive every fourth subframe of the HS-SCCH channel for thenetwork that SIM2 104 is on. SIM2 thus has the DRX pattern 310.

FIG. 4 is a timing diagram 400 that shows the overlap in the SIM1 DRXpattern 306 and the SIM2 DRX pattern 310. In particular due to thetiming similarities in the SIM1 DRX pattern 306 and the SIM2 DRX pattern310, each pattern has substantial overlap. One specific example is thetiming overlap 402, which is about 60% overlap between SIM1 102 and SIM2104. The timing overlap 402 repeats regularly, each time both SIM1 102and SIM2 104 are configured to be active and receiving on the radioresource.

The time sharing of the radio frequency resources support multiple SIMoperation in the user equipment 100. However, this time sharing cancause inefficiencies in responding to wake-up paging signals and ingeneral receiving data while connected. This is particularly true whenthe multiple SIMs have significant overlap in reception timing, as shownin the examples in FIGS. 3 and 4. More specifically, the discontinuousreception parameters have established that both SIMs are supposed to bereceiving at the same time (i.e., during the overlap 402), but cannot doso because the radio resources are shared and only permit access one SIMat a time. As a result, when there is overlap, one SIM cannot receivepages (e.g., in the HS-SCCH) or data because the other SIM is activeinstead.

To enhance the discontinuous modes of operation, the system logic 114determines the amount of overlap in DRX or DTX cycles between SIM1 andSIM2 (and optionally additional SIMs if present in the user equipment100) and attempts to shift the DRX pattern, DTX pattern, or both toenhance the discontinuous mode of operation. In one implementation, thescheduling instructions 122 determine whether the DRX or DTX patternsmeet predetermined efficiency criteria 130.

Examples of efficiency criteria include: whether there is DRX or DTXoverlap, whether overlap is less than a threshold percentage (e.g., 10%)of overlap, whether fewer than ‘n’ subframes overlap in any amount outof every ‘r’ subframes, or whether at least some number of subframe,chip, timing or other gap exists between DRX or DTX accesses fordifferent SIMs. When the efficiency criteria 130 is not met, for examplewhen the amount of overlap exceeds an overlap threshold, the systemlogic 114 may then attempt to shift the DRX pattern, DTX pattern, orboth (when they may be shifted independently under a given communicationstandard), to satisfy the efficiency criteria 130 for the discontinuousmode of operation.

Shifting the DRX/DTX patterns may include negotiating various parameterswith the network controllers (e.g., the Node B 128 and Node B 129) forany of the SIMs in the user equipment 100. For example, the schedulinginstructions 122 may negotiate the UE_DTX_DRX Offset parameter with theNode B 128 to reach the enhancement goal of reducing DRX overlap betweenSIM1 102 and SIM2 104 to less than a predetermined percentage. Thenegotiation may include, as one example, the scheduling instructions 122communicating a desired UE_DTX_DRX Offset for SIM1 102 or for SIM2 104to the Node B 128, and receiving acknowledgement from the Node B 128that the UE_DTX_DRX Offset is accepted and may be used going forward.The negotiation may additionally or alternatively include, as anotherexample, the scheduling instructions 122 forcing a connection (e.g., aphone call or data connection) currently handled by SIM1 102 or SIM2 104to drop, even though there are no particular quality or performanceissues with the connection itself. As a result, when the Node B 128re-establishes the call, the Node B 128 may specify a differentUE_DTX_DRX Offset parameter that results in more efficient discontinuousmode operation. The user equipment 100 may force the connection to dropas often as desired in order to obtain a more suitable UE_DTX_DRX Offsetparameter.

A third way to negotiate the DRX/DTX operation involves the networkmessages that carry discontinuous mode parameters or that otherwisespecify discontinuous mode configuration. In particular, the schedulinginstructions 122 may analyze the discontinuous mode parameters todetermine whether the resulting DRX/DTX patterns meet the efficiencycriteria 130. If the DRX/DTX patterns do not meet the efficiencycriteria 130, then the scheduling instructions 122 may send (e.g,through a RRC layer message) a status message to the Node B 128 thatindicates Configuration Failure. In other words, the user equipment 100may inform the Node B 128 that the user equipment 100 cannot set thediscontinuous mode parameters provided by the Node B 128. The statusmessage may also include a Failure Cause, for example, that thesuggested discontinuous mode parameters would result in inefficientoperation. The Node B 128 may respond to such a message by providingdifferent discontinuous operational mode parameters, asking the userequipment 100 to send suggested discontinuous mode parameters to theNode B 128, or in other ways. One benefit of the Configuration Failedstatus message approach is that is does not force a call to drop.

In other implementations, the scheduling instructions 122 may negotiateother DTX/DRX parameters individually or in combination in an effort toenhance discontinuous mode operation and reach the enhancement goal. Asexamples, the scheduling instructions 122 may attempt to negotiate theUE DTX cycle 1, UE DTX cycle 2, UE DPCCH burst_(—)1, or UE DPCCHburst_(—)2 parameters for SIM1 102 or SIM2 104 individually or incombination (along with UE_DTX_DRX Offset).

FIG. 5 is an example timing diagram 500 that shows the effect of theuser equipment 100 negotiating a change the DRX parameters. In thisexample, the scheduling instructions 122 have caused the user equipment100 to communicate with the Node B 129 responsible for SIM2's network.The scheduling instructions have issued, for example, a parameter changerequest message to the Node B 129, requesting that UE_DTX_DRX_Offset forSIM2 104 be set to a value of 1. This causes the shift by one slot inthe SIM2 DRX reception to obtain the new SIM2 DRX reception pattern 502.

FIG. 6 shows a timing diagram 600 showing the result of the shift in theSIM2 DRX pattern. Instead of DRX overlap, there is now a DRX gap 602.The DRX gap 602 may, for example, provide sufficient time for the userequipment 100 to switch radio access between SIM1 102 and SIM2 104 sothat both SIMs can receive using the shared radio resources. As aresult, both SIM1 102 and SIM2 104 have enhanced ability to receivepages, data, and other communications. Note that the DRX patters may beshifted by more than one slot, any may be reconfigured in many differentways. For example, if the DRX gap 602 does not provide sufficient timeto allow the radio resource to switch to SIM2, then the user equipment100 may instead try to negotiate a DRX offset that increases the DRX gap602 to any degree needed to allow SIM2 to access the radio resource (andto satisfy the efficiency criteria 130).

Similar inefficiencies may arise if the DTX patterns for SIM1 102 andSIM2 104 overlap, and the system logic 114 may similarly request ornegotiate changes to the DRX/DTX parameters to reach any desiredefficiency criteria because of DTX pattern overlap. FIG. 7 shows anexample timing diagram 700 that continues the example shown in FIG. 2.In particular, FIG. 7 shows the DTX overlap 702 between the SIM1 DTXpattern 204 and the SIM2 DTX pattern 208. The entirety, 100%, of theSIM1 DTX pattern 204 overlaps with the SIM2 DTX pattern 208. Conversely,about 33% of the SIM2 DTX pattern 208 conflicts with the SIM1 DTXpattern 204. In this scenario, SIM1 102 cannot transmit at all, if SIM2104 has the radio access, and SIM2 104 cannot use its full DTXallocation if the user equipment 100 will allow SIM1 102 to access theradio resource with SIM2 104.

FIG. 8 shows a timing diagram 800 in which the user equipment 100 hasnegotiated with the Node B 129 to shift the SIM2 DTX pattern ahead threesubframes, e.g., UE_DTX_DRX_Offset=3. The SIM2 DTX burst previously hadthe pattern 802, but has been shifted to pattern 804. As a result, theDTX overlap 702 has been eliminated, and each SIM may transmituninterrupted by the other.

FIG. 9 shows discontinuous mode enhancement logic (DMEL) 900. The systemlogic 114, scheduling instructions 122, or other parts of the userequipment 100 may implement the enhancement logic 900. The DMEL 900obtains the DTX/DRX parameters for SIM1 (902) and for SIM2 (904). TheDMEL 900 may then determine the DTX pattern, DRX pattern, or both forSIM1 102 and SIM2 104 (906). Given the DRX/DTX patterns, the DMEL 900determines whether the DRX/DTX patterns meet the efficiency goal definedin the user equipment 100 (908). For example, the DMEL 900 may determinewhether there is any overlap in the DRX patterns or in the DTX patterns.

If the DMEL 900 determines for any reason to shift the DTX/DRX patterns(910), then the DMEL 900 determines which DTX/DRX parameters tonegotiate (912). There may be many such parameters operating together,as described above for example, that determine the DTX/DRX patterns. Asone example, the DMEL 900 may determine a new value forUE_DTX_DRX_Offset that avoids overlap in the DRX pattern, the DTXpattern, or both.

The DMEL 900 communicates a negotiation message to the supervisingnetwork controller (e.g., to the Node B 128 or 129) that specifies thedesired DTX/DRX parameters. The DMEL 900 receives a response from thenetwork (916). If the negotiation was successful then the DMEL 900 mayset and implement the new DTX/DRX parameters (918). Or, if no furtherattempts are desired, then the process may end. Otherwise, the DMEL maytry again, try different parameters, or different network controllers(920). For example, rather than shifting the DRX pattern for SIM2through negotiation with the Node B 129, the DMEL 900 may instead try toshift the DRX pattern for SIM1 through negotiation with the Node B 128.Furthermore, the DMEL 900 may receive (e.g., in the response from thenetwork) suggestions for parameter values or combinations of parametervalues that the network can implement. The DMEL 900 may chose among thesuggested parameters values and respond to the network controller withits selection.

FIG. 10 shows an example of a network controller 1000 (e.g., the Node B128) that supports DTX/DRX negotiation. The network controller 1000includes a communication interface 1002, processors 1004, and a memory1006. The hardware and software in the network controller 1000 may beimplemented as a UMTS Node B, GSM base station, or other type of networkcontroller.

The network controller 1000 is extended to include logic for handingDTX/DRX negotiation with user equipment. For example, the networkcontroller 1000 may include DTX/DRX parameter negotiation logic 1010.The network controller 1000 may also operate with respect to aparticular set of communication standard rulesets 1016, which may beextended to include DTX/DRX parameter negotiation. For example, inaddition to communicating the UE_DTX_DRX_Offset to the user equipment,the network controller 1000 may also receive negotiation messages 1012from user equipment, determine whether the requested DRX/DTX parametersin the negotiation messages 1012 are permissible in view of the rulesets1016, and prepare and respond to the user equipment with negotiationresponse messages 1014.

FIG. 11 shows an example of the DTX/DRX parameter negotiation logic(PNL) 1010 that may be implemented at the network controller 1000. ThePRL 1010 receives a negotiation message from the user equipment thatcontains suggested DRX/DTX parameters, such as a suggested new value forUE_DTX_DRX_Offset for a particular user equipment SIM (1102). The PNL1010 obtains the suggested parameters from the message (1104). The PNL1010 determines whether the suggested parameters are acceptable (1106).For example, the PNL 1010 may determine whether the suggested parametersmeet the criteria set forth in the communication standard ruleset 1016,and will be acceptable for (e.g., not cause interference with) ongoingcommunications with other user equipment served by the networkcontroller 1000.

If the suggested parameters are acceptable, then the PNL 1010 may setand implement the suggested parameters for the user equipment SIM(1108). The PNL 1010 prepares a negotiation response message indicatingthat the parameters were acceptable (1110) and sends the negotiationresponse message back to the user equipment that originated thenegotiation message (1112).

If the suggested parameters are not acceptable, then the PNL 1010 maydetermine if there are DRX/DTX parameter alternatives that it cansupport for the user equipment and the SIM (1113). If so, the PNL 1010may prepare the response message and specify the alternate DRX/DTXparameters (1114). If there no alternate options, then the PNL 1010 mayprepare a response message indicating that the suggest parameters arenot acceptable and that there are no alternatives available (1116).

The techniques described above are not limited to any particularcommunication standard, DRX/DTX parameters, control or communicationchannels, frame structures, or slot structures. Instead, the techniquesdescribed above are applicable to any shift of DTX/DRX patterns toachieve any desired efficiency goal in a communication system.

The methods, devices, techniques, and logic described above may beimplemented in many different ways in many different combinations ofhardware, software or firmware or both hardware and software. Forexample, all or parts of the system may include circuitry in acontroller, a microprocessor, or an application specific integratedcircuit (ASIC), or may be implemented with discrete logic or components,or a combination of other types of analog or digital circuitry, combinedon a single integrated circuit or distributed among multiple integratedcircuits. All or part of the logic described above may be implemented asinstructions for execution by a processor, controller, or otherprocessing device and may be stored in a tangible or non-transitorymachine-readable or computer-readable medium such as flash memory,random access memory (RAM) or read only memory (ROM), erasableprogrammable read only memory (EPROM) or other machine-readable mediumsuch as a compact disc read only memory (CDROM), or magnetic or opticaldisk. Thus, a product, such as a computer program product, may include astorage medium and computer readable instructions stored on the medium,which when executed in an endpoint, computer system, or other device,cause the device to perform operations according to any of thedescription above.

The processing capability of the system may be distributed amongmultiple system components, such as among multiple processors andmemories, optionally including multiple distributed processing systems.Parameters, databases, and other data structures may be separatelystored and managed, may be incorporated into a single memory ordatabase, may be logically and physically organized in many differentways, and may implemented in many ways, including data structures suchas linked lists, hash tables, or implicit storage mechanisms. Programsmay be parts (e.g., subroutines) of a single program, separate programs,distributed across several memories and processors, or implemented inmany different ways, such as in a library, such as a shared library(e.g., a dynamic link library (DLL)). The DLL, for example, may storecode that performs any of the system processing described above. Whilevarious embodiments of the invention have been described, it will beapparent to those of ordinary skill in the art that many moreembodiments and implementations are possible within the scope of theinvention. Accordingly, the invention is not to be restricted except inlight of the attached claims and their equivalents.

What is claimed is:
 1. A method comprising: determining a firstsubscriber identity module (SIM) discontinuous mode pattern; determininga second SIM discontinuous mode pattern; determining that the first andsecond discontinuous mode patterns fail to meet an efficiency criteria;and negotiating a change to the first SIM discontinuous mode pattern,the second SIM discontinuous mode pattern, or both.
 2. The method ofclaim 1, where negotiating comprises: negotiating between user equipmentand a network controller that supplies a discontinuous mode parameter tothe user equipment.
 3. The method of claim 1, where the changecomprises: a shift in: the first SIM discontinuous mode pattern, thesecond SIM discontinuous mode pattern, or both.
 4. The method of claim1: where: determining the first SIM discontinuous mode patterncomprises: determining a first SIM discontinuous receive (DRX) pattern;and determining the second SIM discontinuous mode pattern comprises:determining a second SIM DRX pattern.
 5. The method of claim 1, where:determining the first SIM discontinuous mode pattern comprises:determining a first SIM discontinuous transmit (DTX) pattern; anddetermining the second SIM discontinuous mode pattern comprises:determining a second SIM DTX pattern.
 6. The method of claim 1, wherenegotiating comprises: sending a message to a network controllerrequesting a change to a discontinuous mode parameter that influencesthe first SIM discontinuous mode pattern, the second SIM discontinuousmode pattern, or both.
 7. The method of claim 1, where negotiatingcomprises: communicating a negotiation message to a network controller,the negotiation message comprising a suggested value for a discontinuousmode parameter that influences the first SIM discontinuous mode pattern,the second SIM discontinuous mode pattern, or both; and receiving aresponse message from the network controller that indicates whether thesuggested value is accepted.
 8. An apparatus comprising: a radiofrequency interface; and system logic in communication with the radiofrequency interface, the system logic configured to: determine a firstsubscriber identity module (SIM) activity period within a discontinuousmode pattern for a first SIM; determine a second SIM activity periodwithin a discontinuous mode pattern for a second SIM; and when the firstSIM activity period and the second SIM activity period have an overlap,communicate a discontinuous mode parameter message through the wirelesscommunication interface to a network controller to attempt to make achange to the first SIM activity period, the second SIM activity period,or both.
 9. The apparatus of claim 8, where the parameter messagecomprises: a suggested parameter value for a discontinuous receive (DRX)mode pattern.
 10. The apparatus of claim 8, where the parameter messagecomprises: a suggested parameter value for a discontinuous transmit(DTX) mode pattern.
 11. The apparatus of claim 8, where thediscontinuous mode parameter message specifies a pattern offsetparameter.
 12. The apparatus of claim 8, where the discontinuous modeparameter message specifies a pattern offset parameter that causes thechange.
 13. The apparatus of claim 12, where the change comprises ashift by a number of subframes specified by the pattern offsetparameter.
 14. The apparatus of claim 8, where the system logic isfurther configured to: receive a response message from the networkcontroller, the response message comprising a network controllersuggested parameter change for addressing the overlap; and implement thenetwork controller suggested parameter change.
 15. An apparatuscomprising: a radio frequency (RF) communication interface; schedulinglogic in communication with the RF communication interface, thescheduling logic operable to: obtain first discontinuous receive (DRX)parameters for a first subscriber identity module (SIM) and determine afirst SIM DRX pattern from the first DRX parameters; obtain seconddiscontinuous receive (DRX) parameters for a second subscriber identitymodule (SIM) and determine a second SIM DRX pattern from the second DRXparameters; determine whether the first SIM DRX pattern and the secondSIM DRX pattern fail to meet an efficiency criteria; select anegotiation technique from multiple available negotiation techniques forattempting to modify the first SIM DRX pattern, the second DRX pattern,or both; and carry out the negotiation technique.
 16. The apparatus ofclaim 15, where the negotiation technique comprises: forcing a calldrop.
 17. The apparatus of claim 15, where the negotiation techniquecomprises: communicating a status message to a network controller, thestatus message indicating a configuration failure of the first DRXparameters, the second DRX parameters, or both.
 18. The apparatus ofclaim 15, where the negotiation technique comprises: communicating anegotiation message to a network controller, the negotiation messagespecifying a suggested value for a selected parameter among the firstDRX parameters, the second DRX parameters, or both.
 19. The apparatus ofclaim 18, where the selected parameter comprises a discontinuous modeoffset parameter.
 20. The apparatus of claim 18, where the selectedparameter comprises a Universal Mobile Telecommunications System (UMTS)UE_DTX_DRX Offset parameter.